public class Double11 {
    public static void main(String[] args) {
        // 赋值，总价格为10000，满减门槛为400，每次满足门槛后减50，无门槛200.3
        int total = 10000;
        int full = 400;
        int bargain = 50;
        double free = 200.3;
        // 先算无门槛优惠
        double first = total - free;
        // 计算满减次数
        int times = (int) (first / full);
        // 计算满减优惠
        double reduction = bargain * times;
        // 计算最终价格
        double fin2 = first - reduction;
        // 在系统中输出结果
        System.out.println(fin2);
    }
}